An integrated circuit (IC) may be manufactured by repeatedly forming patterns on a workpiece using lithography. Lithography is a process for transferring a pattern from a transfer layer (e.g., a reticle) to a workpiece, and is repeatedly performed during the manufacture of an IC. In order for an IC to function correctly, it's important to minimize alignment error between the workpiece and the transfer layer. Contributors to alignment error include, for example, distortion of the workpiece and a tool calibration.